The present invention relates to a system for controlling the lamina size in a raw material treatment process for tobacco leaves.
In general tobacco production process, tobacco leaves raw materials are separated each other and then are provided with a flexibility by the addition of water and steam from a humidity controller. Thereafter they are stripped into parenchyma (hereafter referred to as laminae) and veins (hereafter referred to as ribs) and separated into the laminae and ribs by separating machines. The laminae are dried to possess 12% of water content for avoiding change in quality and molding during a long term storage and then packed in a barrel or other container (abovementioned process be referred to as a raw material treatment process). The packed laminae are stored for a long time for maturing. The laminae which have finished maturing are threshed into cut cigarette after the steps of leaf orientation, blending and flavoring.
During the raw material treatment process, the tobacco leaves are stripped into laminae and ribs. The degree of this stripping gives a large influence upon a raw material yield and product quality. That is, the tobacco leaves are subjected to a great mechanical action when they are stripped into laminae and ribs. Accordingly insufficient separation between laminae and ribs is accomplished, or conversely excessive separation is accomplished so that the tobacco leaves are finely divided depending upon the physical properties possessed by the tobacco leaves. The physical properties depend on largely the water content and temperature.
Accordingly it is important to control a factor which gives influence upon the quality, that is, a mechanical impact force applied upon the tobacco leaves in a rib removing machine to that the impact force have an amplitude suitable for the tobacco leaves.
These controls have heretofore been manually carried out. This manual technique includes adjusting the mechanical impact applied upon the tobacco leaves in the rib removing machine to a suitable value by replacing a basket with that having a different pitch of grid.
It is practically difficult to replace the baskets of the rib removing machine to match the constantly varying inherent physical properties of the tobacco leaves, since they largely vary according to the production place, weather conditions of the production year. Therefore it is very difficult to control the quality by controlling the lamina size to an optimum value.